We know precisely which patients and when they should have an imaging test to evaluate a Head Injury (HI). But in those patients on anticoagulant and / or antiaggregant treatment we do not know the exact incidence of early and late hemorrhagic lesions, and there is no specific recommendation on how long they should remain under observation in the emergency department if no initial lesions are evident. Our goal is to try to answer these two questions.

MATERIAL: Prospective study of patients treated of HI in the Emergency Department (ED) and to whom an image test is performed (cranial CT scan). Collection of demographic, clinical, analytical, image tests, and observation time in the emergency department (from admission to medical discharge)

METHODS: Separation of subjects included in the study in 4 cohorts: patients without anticoagulant and / or antiaggregant treatment; patients with antiplatelet therapy (ASA and / or clopidogrel); patients with anticoagulant treatment with acenocoumarol and INR <2; and patients on anticoagulant therapy with acenocoumarol and INR> = 2 or patients on treatment with direct thrombin inhibitors (dabigatran), or inhibitors of factor Xa (rivaroxaban, apixaban, edoxaban) or patients on treatment with low molecular weight heparins (LMWH) ) Follow-up through analysis of clinical history and telephone interview at 2, 7, 15, 30, 60 and 90 days.

Statistical analysis of the results.

Inclusion Criteria:

• HI attended at ED
• Head CT performed as recommended by clinical guides
• Contact data available (phone number)

Exclusion Criteria:

• Patients not able for follow up (foreigners or tourists or whatsoever whom are not going to stay on the country for at least 3 months)

Patients treated by HI in the Emergency Department (ED) and to whom an imaging test is performed (cranial CT scan)